Noiseless type action for typewriters



May 1o, 1932. y 1A. RAMUS 1,857,741

NOISELESS TYPE ACTION FOR TYPEWRITERS Filed Feb. 13, 1929 'jf/11'@ #HD7-nays Patented May 10, 1932 MNITED 'STA TES PATENT OFFICE? JAMES RAMUS, OF OAKLAND, CALEFORNIA NOISELESS TYPE ACTION`FOR TYPEWBITERS Application filed February 13, 1929. Serial No. 339,534. i

simple but eicient type action which will beA readily applicable to many standard makes of typewriters now in commercial use, and which will decrease and practically eliminate 10 noise in the operation of a typewriter.

Another object of the invention is to pro- `vide type action of the class above referred to wherein the speed, lightness of touch and ease of operation of the typewriter may be increased, the touch being adjustable within, of course, certain limits.

` A further object is to provide a so-called lnoiseless type actionwherein the noise from the striking of the type against the platen is greatly decreased by the use of a yieldingly mounted type head carried at the free end of the type bar.

Still a.l further object is to provide in mechanism of the class described, means for greatly reducing the noise from the engagement ofY the intermediate portion of the type bar with the fixed segment ring on the typewriter.

l `These and other objects and advantages of the invention will be apparent from thefollowing description made in connection with the\ accompanying drawings, in which like reference characters refer to similar parts throughout the several views and in which,

Fig. 71 is a fragmentary front elevation showing the application of my invention upon a standard typewriter manufactured by thel Underwood Typewriter Company. A

Fig. 2 is a vertical cross section of tlie same, showing the position of the type bar when striking the platen in full lines and inoperative position of the type bar in dotted lines; Fig. 3 is a side elevation, on a greatly en-- larged scale, of the upper end of one of thev type bars with my slidable type head thereon; Fig. 4 is a vertical section taken on the y line 4-4 of Fig. 3;

Fig. 5 is a cross section taken on the line" of the type bar showing the type carried thereby; and n Fig. 7 is a fragmentary cross section taken on the line 7-7 of Fig. 1, illustrating my means cushioning the impact ofthe intermediate portion of the type bar with the fixed segment ring.

' While my inventionis applicable to several kinds of standard typewriters, the embodiment herein illustrated is shown applied to the standard type of typewriter now manufactured by the Underwood Typewriter Company. Inthe drawings, the usual metal segment,.indicated as an entirety by the letter S, is shown having the radially slotted guide portions 10 adjacent lits lower edge between which the several type'bars B are pivotally mounted. As shown, the type bars are fulcrumed adjacent their linner fends upon a segment rod 11 passing circumferentially through said slotted guide portions 10 at the rear thereof. and engaged in the usual fashion by the slotted portions of the type bars. Type bars B have short projecting operating arms 12 extending below the segment rod 11 and which are connected for-operation with the type bar links 13 connected to the key levers (not shown). The usual upright type guide 14 is centrally mounted at the upper edge Vof segment S having the outturned converging guide jaws 14a, between which the f upper ends of the several type bars are adaptedgto move. Av platen roll P of usual style is shown, having wound thereon t-wo sheets of typewriter paper with a carbon sheet interposed between the two. The free ends of my type bars B are constructed somewhat' p slidabletypehead 15 is mounted thereon.

Type head 15, as clearlyshown in Figs. 3, 4 and 5, comprises a U-shaped member straddling the flat sides of type bar' B and having a flat inner end or edgela on which' the type T is carried. The sides of type head 15 extend parallel and are provided with enlarged recesses 150 of oblong shape leaving upper and lower arms 15b extending transversely of the type bar and slidably engaging,

rectangular guide plates 16 which are disposed on opposite flat sides ofthe free end of the type bar and rigidly attached thereto. sharp impact of the type against the paper The longitudinal edges of guide plates 16 and platen will be resiliently cushioned byV preferably have beveled engagement with the slight yielding movement ofslidable type the arms 156, and said guide plates 16 may be head 15, said type head sliding laterally upon 6 rigidly attached to the type bar -by any suitthe free end of the type bar against the presable means, such as by the rivets 17. I prosure of leaf spring 21. Since the type head l vide means for adjusting the width of guide is precisely guided by the beveled engagement plates 16, which, as shown, comprises beveled between the longitudinal edges of guide plate headed screws 18 working in slotted portions 16 and the type head arm 156, the type will 1o 16a which extend longitudinally of lsaid guide strike the paper as precisely as if it were plates and transversely of the typewriter. A rigidly attached to the free end of the type ack tie plate 19 is provided for the type head bar. In the event that through continuous and may be welded or otherwise secured to the rear or outer ends of the type head arms 15 156, limiting the forward and inward movement of said type head and preferably having inturned extremities 19a which surround the corners of the extremities-of arms 156. A rectangular slot (see Fig. 5), is provided 2o centrally of tie plate 19 through which a small ear 20 integrally formed or rigidly carried by the free end of the type bar may pass, Said ear having pinned Aor otherwise secured thereto a saddle 21a which rigidly carries a 25 double leaf spring 21, `the inner edges of said saddle preferably extending through the slot v in tie plate 19 and abutting against the outer edge of the type bar. Ieaf spring 2l presses against the tie plate 19 to yieldingly hold the type head in extended 1forward or inward position. v

In the operation of the usual type bars of typewriters, the intermediate portions of their forwardedges strike against the segment ring SR carried by vsegment S and disposed concentrically with the point'of writing andare limited in movement thereby. This sharp striking produces considerable noise. I provide a resilient contact plate 22 40 of segmental shape which, as illustrated, is of laminated or multi-ply construction and l has an anchoring portion 22a and an outwardly and upwardly extending contact portion 226 circumfere tially alined with the segment ring SR. f desired, a contact tread 23 of some relatively non-resonant material, Such as copper may be affixed to the inner surface of the contact portion 226 of plate 22. I prefer to slot Contact portion 226 of my resilient plate and tread 23 radially from the point of writing of the typewriter to lessen the chance of said plate cracking from continuous, hard usage. A suitable clamping plate 24 of arcuate shape engages the anchoring portion 22a of resilient plate 22 and may be secured to segment S by suitable screws 25, plate 22 being so disposed that the contact portion 226 vis spaced slightly from the segment ring SR. o Operation j The operation of my improved mechanismL Ymi against the paper on the platen cylinder, th

wear sliding engagement between plate 16 and the type head becomes too free, the slack may be quickly taken up by adjusting the beveled headed screws 18, which will spread plate 16.

The slight yielding action of the type head, of course, lightens the touch of the typewriter depending upon the tension of the particular spring 21 utilized.. Thus, if it is desired to use the typewriter for heavy carbon work leaf springsc21 of greater tensionI may l be used than if this work isnot required. It.

will thus be apparent that the requirement of the touch of the typewriter is adjustable within, of course, certain limits. The rey silient cushioning of the impact blow of the type greatly reduces this source of noise.

Almost simultaneously with the impact of the type against the platen, the intermediate inner longitudinal edge of the type bar strikes against the resilient plate 22, the yielding action of said plate cushioning the blow and causing the contact portion 226 of the plate, or relatively non-resonant tread 23, if the latter -is utilized, to strike the segment ring. This structure greatly reduces the noisefrom s the striking of the segment ring and moreover lightens the touch of the typewriter and con- (siderably accelerates the rebound Vof the typebar from fheo laten, Adue to the resilient reiex action of t e plate 22. i From the foregoing description, it will be seen that my noiseless type action eliminates the olfensivevnoise of a typewriter at the two points from which in most typewriters, practically all noise is produced. It will also be seen that with my structurethe touch and operation of the typewriter is lightened and accelerated. 'It will be obvious that my mechanism may be quickly applied as an attachment to several different kinds of typewriters now in lcommercial use by simply substituting my t pe bars, type heads and the other elements-o my structure and by adding my segment platelto the usual segment now in use. It will be equally@ apparent that my mechanism is adapted to be builtinto the typewriters at the place of manufacture. The increased number of parts required loo by my invention is small and the cost is nominal. In actualpractice the device hasybeen demonstrated with high eiiciency.

It will, of course, vbe understood that varitending l ous changes may be made in the form details, arrangement and proportions of the parts without departing from the scope of the invention.

What is claimed is:

1. In a typewriter, a swingable type bar, a type head slidably connected with sald t pe bar for movement transversely of said ar, means associated with said type bar for yieldingly holding said type head in extended forward position, anda' resilient segment plate havinga series of transverse slits exfrom the outer ed e thereof and formin independently opera le resilient sections a apted to engage the intermediate portion of said type bar for cushioning the impact of said type bar and cooperating with the slidable t pe head to decrease the noise in the impact o the type head against the platen.

2. In a typewriter, a swingable type bar terminating in a strilng end disposed edge- Wise to the platen of the typewriter, said striking end having straight guide elements disposed externally on its opposite sides and extending transversely of said bar, a t pe head embracing said striking end and s `d ably connected with said guide elements and having a forward end carrying type and resilient means for normally urging said type head lto extreme forwardly projected position.

3. In a typewriter, a swingable type bar terminating in a striking end disposed edge-` wise to the platen of the typewriter, s ald striking end having externally disposed guide plates or ribs on opposite sides thereof extending transversely of said bar, a type head straddling the outer end of said type bar and having recessed portions in the sides thereof slidably engaging said guide plates and having a forward end carrying type, and a resilient element secured to said striking end and engaging said type head to urge the same to extreme forwardly projected position.

4. In a typewriter,` a swingable type bar terminating in a striking end disposed edgewise to the`platen of the typewriter, said striking end having externally disposed guide plates or ribs on opposite sides thereof extending transversely of said bar, a type head straddling the outer end of said type bar and having recessed portions in the sides thereof slidably engaging said guide plates and having a forward end carrying type, a bowed spring secured to the back edge of the outer end of said type bar extending longitudinall thereof and engaging at its ends rear4 por- 'tions of said type head for normally urging the same to extreme forwardly projected position. i.

In testimony whereof I aiiix my signature.

JAMES A. RAMU S. 

